.\" $NetBSD: stat_flags.3,v 1.8 2012/09/19 23:22:56 wiz Exp $
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.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Christos Zoulas.
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.Dd September 20, 2012
.Dt STAT_FLAGS 3
.Os
.Sh NAME
.Nm string_to_flags ,
.Nm flags_to_string
.Nd Stat flags parsing and printing functions
.Sh LIBRARY
.Lb libutil
.Sh SYNOPSIS
.In util.h
.Ft char *
.Fn flags_to_string "u_long flags" "const char *def"
.Ft int
.Fn string_to_flags "char **stringp" "u_long *setp" "u_long *clrp"
.Sh DESCRIPTION
The
.Fn flags_to_string
and
.Fn string_to_flags
functions are used by
programs such as
.Xr ls 1 ,
.Xr mtree 8 ,
.Xr makefs 8 ,
etc., to parse and/or print the
.Dv st_flags field in the
.Xr stat 2
structure.
.Pp
They recognize the following flags:
.Bl -column -offset indent "uappnd " "SF_IMMUTABLE" "xxx"
.It Sy String Ta Sy Flag Ta Sy Description
.It Va arch Ta Dv SF_ARCHIVED Ta file is archived
.It Va nodump Ta Dv UF_NODUMP Ta do not dump file
.It Va opaque Ta Dv UF_OPAQUE Ta directory is opaque in union filesystems
.It Va sappnd Ta Dv SF_APPEND Ta writes to the file may only append
.It Va schg Ta Dv SF_IMMUTABLE Ta file cannot be changed; it is immutable
.It Va snap Ta Dv SF_SNAPSHOT Ta file is a snapshot inode
.It Va uappnd Ta Dv UF_APPEND Ta writes to the file may only append
.It Va uchg Ta Dv UF_IMMUTABLE Ta file cannot be changed; it is immutable
.El
.Pp
The
.Dv SF_APPEND
and
.Dv SF_IMMUTABLE
flags are for the superuser only, whereas
.Dv UF_APPEND
and
.Dv UF_IMMUTABLE
are for the user only.
.Pp
The
.Fn flags_to_string
function converts the bits set in the
.Fa flags
argument to a comma-separated string and returns it.
If no flags are set, then the
.Fa def
string is returned.
The returned string is allocated via
.Xr malloc 3
and it is the responsibility of the caller to
.Xr free 3
it.
.Pp
The
.Fn string_to_flags
function takes a
.Fa stringp
of space, comma, or tab separated flag names
and places their bit value on the
.Fa setp
argument.
If the flag name is prefixed by:
.Dq no ,
then the bit value is placed on the
.Fa clrp
argument.
.Sh RETURN VALUES
.Fn flags_to_string
returns the symbolic representation of flags, the default string, or
.Dv NULL
if allocation failed.
.Pp
.Fn string_to_flags
returns
.Dv 0
on success and
.Dv 1
if it fails to parse the string, setting
.Fa stringp
to point to the first string that it failed to parse.
.Sh SEE ALSO
.Xr chflags 2 ,
.Xr stat 2